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N Hanai

Publications and source records attributed to N Hanai.

At least 91 records · Page 5Linked to original sources

Distribution of a squamous cell lung carcinoma-associated antigen, KA-32, in human tissues and sera defined by monoclonal antibody KM-32.

The distribution of a variant of blood group A antigen recognized by a murine monoclonal antibody, KM-32, generated against human squamous cell lung carcinoma was investigated in various tissues and sera. By immunoperoxidase staining, the antibody was found to react with a number of lung carcinoma tissues of squamous cell carcinoma, adenocarcinoma, and small cell carcinoma, and several other tumor tissues. Positive staining was also observed in a small number of cells of some normal tissues, such as bronchiolar epithelium, gastrointestinal glands, and convoluted tubules of the kidney. The antibody could also be used in detecting macromolecular antigens, designated KA-32, in sera of patients with lung cancer. The antigen level in serum was determined by an inhibition assay using purified KM-32. The higher level of inhibition was seen in sera from over half of patients with lung cancer and patients with benign diseases when compared with those in sera from healthy adults. Purification of the antigen in serum was performed by gel filtration chromatography, immunoaffinity chromatography, and polyacrylamide gradient gel electrophoresis. Purified antigen exhibited a glycoprotein nature, and its molecular weight was estimated at more than 500,000.

ABO Blood-Group System↗

Generation of monoclonal antibodies against human lung squamous cell carcinoma and adenocarcinoma using mice rendered tolerant to normal human lung.

Four murine monoclonal antibodies against human lung carcinoma were generated using a novel immunization procedure. BALB/c mice were rendered neonatally tolerant to normal human lung tissues and subsequently immunized with human lung tumor tissues. The lower level of antibody-reactivity to the tolerogen was seen in the sera of mice rendered neonatally tolerant as compared with the level of reactivity in the sera of nontolerant mice. The mice which maintained a sufficiently tolerant state were selected for hybridoma production. Two monoclonal antibodies, KM-32 and KM-34, were developed from mice immunized with lung squamous cell carcinoma tissues and two other monoclonal antibodies, KM-52 and KM-93, were developed from mice immunized with lung adenocarcinoma tissues. Distribution of antigens detected by the monoclonal antibodies were investigated by enzyme-linked immunosorbent assay using membrane fractions prepared from a number of tumorous and normal tissues and various human normal and tumor cell lines. KM-32 recognized a carbohydrate antigen expressed predominantly on lung squamous cell carcinoma cells and its carbohydrate structure appeared to be associated with blood group A antigen. KM-93 recognized a sialylated carbohydrate epitope on the antigen expressed on lung adeno-carcinoma cells and a few other tumor cells. KM-34 and KM-52 detected protein or glycoprotein antigens and they showed predominant reactivity to lung squamous cell carcinoma and lung adenocarcinoma, respectively. KM-32 and KM-34 antibodies showed complement-dependent cytotoxicity against a lung tumor cell line. These results suggest that the tolerance technique is useful for efficient screening of murine monoclonal antibodies specific to human tumors. The efficacy of these four monoclonal antibodies in diagnosis and therapy of lung cancer will be the subject of a sequential study.

Adenocarcinoma↗

Morphological and immunocytochemical study of rat pancreatic beta cell changes induced by cyclizine.

Wistar rats were treated daily with cyclizine (50-75 mg kg-1) and autopsied every week until the eighth week of the treatment. Although no evident change could be detected by either serum analysis or by light microscopy from the first week to the fourth week, electron microscopy revealed that beta cells showed depletion of secretory granules and cystic dilation of the rough endoplasmic reticulum from the first week. A significantly higher level of plasma glucose and a lower level of plasma insulin than those of untreated rats were recognized from the fifth week. A diabetic pattern was also observed in the glucose tolerance test which was conducted at the seventh week. From the sixth week, large cytoplasmic vacuoles were observed light microscopically in islet cells. Electron microscopic examination revealed that the vacuoles originated from the rough endoplasmic reticulum in beta cells, while no prominent change was found on the Golgi apparatus. In addition to the above findings, immunocytochemical study with anti-insulin serum demonstrated that the staining intensity of the beta cell cytoplasm became weaker (as judged by light microscopy) from the fifth week, but large cytoplasmic vacuoles were stained positively under both the light microscope (PAP method) and the electron microscope (enzyme-labelled antibody method). These findings suggested that the depletion of secretory granules and accumulation of insulin or its precursor in the rough endoplasmic reticulum occurred in beta cells. The diabetogenic effect of cyclizine on rats is discussed with reference to the immunocytochemical findings.

Animals↗

Effects of dimethyl sulfoxide and colchicine on the resorption of experimental amyloid.

The induction of amyloid in C3H mice by either casein solution or complete Freund's adjuvant emulsion with Mycobacterium butyricum was confirmed by partial splenectomy. The animals were autopsied after treatment with dimethyl sulfoxide (550 mg/kg, 50 times), colchicine (0.02 mg/kg, 15--37 times), or saline solution as a control. Detailed histological comparisons of biopsy and autopsy spleens provided evidence that dimethyl sulfoxide was significantly effective in the resorption of amyloid, while in the animals treated with colchicine amyloid deposition was increased. The effect of dimethyl sulfoxide was discussed with reference to the modification of amyloid fibrils.

Amyloid↗

Application of anti lung adenocarcinoma monoclonal antibody recognizing cytokeratin-like cytoplasmic antigen for tumor diagnosis.

An anti lung adenocarcinoma murine monoclonal antibody (MoAb), KM195 (IgG1), was generated using mice which underwent tolerance treatment to normal lung tissues. KM195 was selected from among a number of hybridoma clones because of its advantageous reactivity such as high binding to cell membranes of lung adenocarcinoma tissues and low binding to cell membranes of major normal tissues. In a binding assay using cultured cell lines KM195 was found to bind cytoplasmic antigen in many adenocarcinoma cells. Detailed immunohistochemical analysis using paraffin-fixed tissue sections showed that many adenocarcinoma cells such as gastric cancer, colorectal cancer, pancreatic cancer, mammary cancer, ovary cancer and cervical cancer reacted positively with KM195, as well as lung adenocarcinoma cells. KM195 also positively stained a small number of normal cells found in adult and fetal tissues like lung, intestine, pancreas, liver and kidney. Western blot analysis using membrane fraction of lung adenocarcinoma tissues revealed two major KM195-positive bands which were electrophoresed nearby at molecular weights (M.W.) of 40 Kd. The protein corresponding to the two major bands was purified by immuno-affinity chromatography and sequenced. The amino-terminal 19 residues of the lower band was identified as VLEVDPNIQAVXTQEXEQI, which is identical to that of the human cytokeratin 8 (residues 77 to 95), M.W. 52Kd. The amino-terminal sequence of the upper band was blocked and not determined. To examine the ability of KM195 for tumor imaging, 125I-labeled KM195 was injected i.v. into nude mice bearing SW1116 xenografts. Significantly higher radioactivity was observed in the tumor compared with major organs at days 3 and 5. These data indicate that KM195, which recognizes cytokeratin 8-like cytoplasmic antigen, could be a potential MoAb for use in the immunohistochemical diagnosis and radioimmunodetection of adenocarcinoma.

Adenocarcinoma↗

Development of anti-idiotype monoclonal antibodies for Sialyl Le(a) antigen.

Anti-idiotype monoclonal antibodies (MoAbs) were developed for a carbohydrate antigen, Sialyl Le(a), by immunizing mice with an anti-Sialyl Le(a) MoAb, KM231 (mouse IgG1). The anti-idiotype MoAbs inhibited the binding of KM231 to Sialyl Le(a)-positive mucin protein, but did not affect the binding of another MoAb (mouse IgG1) which recognized a peptide epitope on the same mucin protein. The selected four anti-idiotype MoAbs bound to all of the five anti-Sialyl Le(a) MoAbs examined, but not to other MoAbs developed against Sialyl Le(a)-related carbohydrate antigens such as Le(a), Le(x), and Sialyl Le(x) blood type A, B, H antigens. Immunization of rats with one of the anti-idiotype MoAbs, of which the reactivity was remarkably inhibited by Sialyl Le(a) oligosaccharide, resulted in the induction of antibody (Ab3) to purified Sialyl Le(a) glycolipid. Taken together, one of the anti-idiotype MoAbs developed in this study was the first Ab2 beta-type anti-idiotype MoAb which carried the internal image of Sialyl Le(a) antigen. The positive reaction of tumor cells expressing Sialyl Le(a) antigen with the Ab3 gave rise to the possibility that the anti-idiotype MoAb would become an effective tool for active immunotherapy in patients with Sialyl Le(a)-positive tumor.

Animals↗

Application of anti-sialyl Lea monoclonal antibody, KM231, for immunotherapy of cancer.

A mouse monoclonal antibody (MoAb), KM231 raised against human gastric cancer was found to recognize sialyl Lea -epitope expressed on glycoprotein and glycolipid with high affinity. KM231 reacted with many human gastrointestinal cancer tissues and could detect the antigen shed in sera of cancer patients. The present study was designed to evaluate competence of KM231 for immunotherapy of cancer. We first confirmed that KM231 could probe the cancer cells in vivo by injecting biotinylated KM231 into nude mice bearing human colorectal carcinoma cell, SW1116. Light- and electron-microscopic examination showed that the MoAb was localized in the tumor tissues and bound to the plasma membrane and cytoplasmic endosomes. Imaging studies with 125I-labeled KM231 revealed specific localization of the antibody in SW1116 tumors transplanted into nude mice. From Scatchard analysis of KM231 binding, the number of KM231 molecules bound to per SW1116 cell was calculated approximately 1.9 x 10(6) and the association constant was 1.3 x 10(8) liter/mol. We made KM231-ricin A chain immunotoxin for evaluating the tumoricidal effect of KM231. The immunotoxin exerted strong cytotoxicity toward sialyl Lea-expressing tumor cells specifically in vitro, but not toward sialyl Lea non-expressing cells. The in vivo tumoricidal effect of the immunotoxin was examined on ascites and subcutaneous xenograft tumors in nude mice. Three intraperitoneal injections of the immunotoxin (1.6 x 10(-6) mol) into nude mice bearing SW1116 ascites tumor resulted in extension of survival by 204% compared with controls. Further, repeated intraperitoneal administration of the immunotoxin (1.4 - 2 x 10(-6) mol) significantly inhibited the growth of established subcutaneous tumor (ratio of tumor inhibition = 0.7 - 0.54). These results indicated that KM231 has the ability to probe sialyl Lea-expressing tumor cells in vivo with high efficiency and to become tumoricidal drug when it conjugated with cytotoxic reagents like ricin A chain.

Animals↗

Detailed characterization of reactivities of anti-gastric cancer monoclonal antibodies to carbohydrate antigen.

Four murine monoclonal antibodies (MoAbs), KM191, KM206, KM230 and KM231, raised against gastric cancer exhibited very similar reactivities to human carcinoma cells, whereas their abilities in probing the antigen shed from the cancer cells were quite different. We found in this study that the four MoAbs reacted immunologically with the same monosialo gangliosides derived from a gastric cancer cell line by two-dimensional high performance thin-layer chromatography. When the reactivities of the MoAbs to a number of purified gangliosides or oligosaccharides were examined, the carbohydrate structure of the antigen was determined as sialyl Lea. KM231 exhibited the highest binding avidity to the oligosaccharide and the ganglioside among the four MoAbs. In a comparative study of KM231 and NS19-9, which is a widely used sialyl Lea-reactive MoAb, KM231 bound to the oligosaccharide with higher affinity and detected the antigen in tissue sections with higher sensitivity. In addition, KM231 could detect a small amount of the antigen ganglioside in human gastric normal and cancerous mucosa and in gastric cancer cell lines by HPTLC-immunostaining.

Animals↗